1. Field of the Invention
The present invention relates to a recording tape cartridge rotatably accommodating a single reel around which a recording tape such as a magnetic tape is wound.
2. Description of the Prior Art
A recording tape such as a magnetic tape is widely employed as an external recording medium for a computer. By winding the magnetic tape on a reel and housing the reel in a housing to form a magnetic tape cartridge, only a small space is needed for storage to be able to construct a magnetic tape cartridge, which is able to record a large amount of information.
As seen in FIG. 11, when this magnetic tape cartridge is loaded in a tape drive, a leader pin attached at an end of the magnetic tape is taken up from a take-up opening by a chucking member disposed at the tape drive. The leader pin, which is taken up from a take-up opening of the housing, is lead to a reel of the tape drive through a specific magnetic tape path and is engaged with the reel. Thus, the magnetic tape 10 is wrapped around the reel and computer data are recorded on and played back from the magnetic tape.
Flanges 12A formed at both of the ends of the leading pin 12 protrude from both of the edges, in the width direction of the magnetic tape 10. When the magnetic tape 10 is taken back in the housing 70, the flange 12A held in a housing 70 by being inserted into a holder groove 40, which extends to the take-up opening, and pressed by a plate spring 50. The plate spring 50 comprises a base portion 52, which is fixed to the housing 70, and a pair of arm portions 54, which project from the base portion 52 in parallel. At each end of the arm portions 54, a pressing portion 54A is formed and engages with flanges 12A.
However, making a spring force of the arm portions 54A the same is difficult, and variation occurs. Therefore, as shown by two-dot chain line in FIG. 11, There is a possibility that the leader pin 12 will be slanted by the difference of the spring forces and will not be correctly engaged with the chucking device.
An object of this invention is to solve the above-mentioned problems. Accordingly, an object of this invention is to provide a recording tape cartridge, in which, when the recording tape is taken up by a reel, a leader member, such as a leader pin attached on an end portion of a recording tape, is held at an optimal position inside a housing, and, when the recording tape is wound out from the housing, the leader member is correctly chucked by a chucking member of a tape drive.
A first aspect of this invention for achieving the above-mentioned object is a recording tape cartridge comprising a recording tape; a leader member attached at an end of the recording tape and extending in a width direction of the recording tape; a single reel on which the recording tape is wound; a housing for holding the reel rotatably and including a take-up opening from which the tape is taken up and a holding portion formed adjacent to the opening; and an urging member for urging the leading member and securing the same at the holding portion when the recording tape is taken back in the housing; wherein the urging member including a pressing portion formed continuously in the axial direction of the leading member and contacting both ends of the leading member when the leading member is secured at the holding portion.
The pressing portion of the urging member of the recording tape cartridge is an integrated member formed continuously in the axial direction of the leader member. Therefore, an equal force is applied to both ends of the leading member, and there happens no slanting of the leading member.
Accordingly, since the urging force from the urging member is not different between one end of the leader member and the another, the leader member does not slant because the leader member is held at an optimal position when the recording tape is taken up from the reel. When the recording tape is pulled out from the housing, the leader member is correctly chucked by the chucking member, which is disposed at the tape drive. Therefore, the recording tape is correctly wound around a reel disposed at the tape drive.
As described above, the pressing portion of the urging member extends continuously in the axial direction of the leader member. In other words, the pressing member is formed to be continuous in the axial direction of the leader member and when the recording tape is taken back into the housing, the leader member is secured at the holding portion.
Examples of the recording tape include a magnetic tape used as an external recording medium for computers.
Examples of the leader member include a leader pin, which is a rod-shaped member extending in the width direction of the recording tape and both ends of the leader pin protrude from the edges of the recording tape.
The leader pin can be cylindrical and can have flanges formed at both ends thereof.
In the housing, a take-up opening and a holding portion are formed. The holding portion is formed adjacent to the take-up opening and functions to secure the leader member when the recording tape is taken back into the housing.
The holding portion includes a recess formed on an inner wall of the housing as well as a holding member that is hook-shaped and is mounted on the inner wall of the housing. The holding member can be formed integrally with the housing. It also can be a separately formed member fixed to the inner wall.
The urging member has a function of urging the leader member to secure the same in the holding portion and comprises, at end portions thereof, pressing portions, which contact at least both ends of the leading member. A shape of the pressing portion is not particularly limited, as long as they extend along the width direction of the recording tape.
A plate spring is a preferable example of the urging member in that a plate spring has a simple configuration. The plate spring can have a frame-shape with a central portion of the plate spring cut-out. In addition to the plate spring, an example of the urging member also includes a device comprising a contacting member, an arm member and a spring. The contacting member includes a function of the pressing portion. The contacting member is fixed to one end of the arm member and the other end of the arm member is rotatably mounted on the inner wall of the housing. The spring is disposed between the arm member and the inner wall so that the spring urges the arm member to hold the lead member in the holding portion. Example of the spring includes a coil spring and a plate spring.
A second aspect of this invention for achieving the above-mentioned object is the recording tape cartridge of the first aspect wherein the leader member is a leader pin.
In the recording tape cartridge, the recording tape is pulled out from the housing and rolled into the interior of the drive by both ends of the leader pin being grasped by a checking portion of the derive, and the leader pin being drawn into the interior of the tape drive.
A third aspect of this invention is the recording tape cartridge of the second aspect wherein the holding portion is a pair of recessions formed at a position of an inner wall of the housing adjacent to the take-up opening so as to face to each other with the recording tape therebetween.
In the above tape cartridge, when the recording tape is taken back in the housing, the leader member is secured at a position adjacent to the opening by both ends of the leader member being inserted into the recess. The recess may be groove-shaped. This groove-shaped recess can be referred to as a holding groove. The recess is preferably formed so as to narrow in the direction of the inside of the housing. A recess formed in this way engages with the leader member more securely when the recording tape is taken up into the housing. Since the pair of recesses is formed as the holding portion, parts for forming the holding portion are unnecessary. Accordingly, the number of parts can be reduced and assembly is simple.
A fourth aspect of this invention is the recording tape cartridge of the third aspect wherein the urging member is a plate spring.
A fifth aspect of this invention is the recording tape cartridge of the fourth aspect wherein the plate spring is formed of metal.
In this recording tape cartridge, the leader member passes through a gap between the inner wall of the housing and the pressing portion of the plate spring, overcoming a spring force from the plate spring to be secured in the holding portion when the recording tape is taken back into the housing. When the leading member passes the interval, the leader member is held in the holding portion by the spring force from the plate spring.
When the recording tape is taken up into the tape drive, the chucking device overcome the spring force from the plate spring to draw the leader member into the tape drive.
The plate spring can be produced by bending a rectangular, thin metal sheet and the pressing portion can be formed at one end of the bent, thin, metal sheet. Moreover, the plate spring can be fixed to an interior wall of the housing by disposing a securing groove, which secures the other end of the plate spring, on the interior wall of the housing, and inserting the other end into the securing groove.
The recording tape cartridge is an example in which the holding portion is a pair of recesses and the urging member is a plate spring.
A sixth aspect of this invention is the recording tape cartridge of the fifth aspect wherein the plate spring has a frame-like shape and an opening in a central portion thereof.
By forming an opening in its central portion, the spring force of the plate spring can be easily reduced. Therefore, when a reduced spring force is required, the above-mentioned plate spring is preferable as the urging member.
A seventh aspect of this invention is the recording tape cartridge of the sixth aspect wherein the recording tape is a magnetic tape.
In the above recording tape cartridge, when the magnetic tape is wound on the reel, the leader member is held in the housing in a most optimal position. When taking up the magnetic tape, a chucking device of a tape drive correctly chucks the leader member and the magnetic tape taken up from the housing is correctly wound on the reel of the tape drive.
Therefore, a trouble such as a reading error or a jamming caused by incorrect taking up of the magnetic tape on the reel can be avoided and this aspect provides a reliable magnetic tape cartridge that can be used as an external recording medium for a computer.
An eighth aspect of this invention relates to the recording tape cartridge of the fourth aspect wherein the plate spring is formed integrally with the housing.
The housing of a recording tape cartridge is usually formed by injection moulding of a thermoplastic resin. In the recording tape cartridge of this aspect, its plate spring can be moulded integrally with the housing. Therefore, the structure of the recording tape cartridge of this aspect is simple. Additionally, there is no need to dispose an under-cut portion in a mould for moulding arm portions and the mould can be easily parted because the pressing portion of the plate spring is not a pair of arms but a portion continuously formed in the axial direction of the leader member.
A ninth aspect of this invention is the recording tape cartridge of the eighth aspect wherein the recording tape is a magnetic tape.
A tenth aspect of this invention is the recording tape cartridge of the second aspect wherein the urging member is a plate spring.
An eleventh aspect of this invention is the recording tape cartridge of the tenth aspect wherein the plate spring is formed of metal.
A twelfth aspect of this invention is the recording tape cartridge of the eleventh aspect wherein the plate spring has a frame-like shape and an opening in a central portion thereof.
A thirteenth aspect of this invention is the recording tape cartridge of the twelfth aspect wherein the recording tape is a magnetic tape.
A fourteenth aspect of this invention is the recording tape cartridge of the tenth aspect wherein the plate spring is formed integrally with the housing.
A fifteenth aspect of this invention is the recording tape cartridge of the fourteenth aspect wherein the recording tape is a magnetic tape.